Acute poisoning is a common cause of morbidity and mortality in children and adults. However, if ingested poison can be removed from the gastrointestinal track before being absorbed, the risk of severe poisoning is reduced. One method of removing ingested poison is that of oral gastric lavage in which the gastrointestinal track or stomach is successively irrigated and aspirated through a lavage tube inserted along the patient's gastrointestinal track to the stomach.
A common method of oral gastric lavage is described in U.S. Pat. No. 5,667,500 which uses parallel connected syringe cylinders having plungers and valves to allow both irrigation and aspiration through a single nozzle connected to a single lumen pliable lavage tube. Such a system requires continual, manual pumping by an attendant.
An improvement is taught in U.S. Pat. No. 5,890,516 which provides an aspiration valve allowing the use of an in-wall vacuum system, such as is commonly found in hospitals, for operation of the lavage system without manual pumping. In this device, a double lumen flexible tube is provided, one lumen delivering an irrigation liquid and the second being used for aspiration through the in-wall vacuum system. The aspiration valve allows continual adjustment of the aspiration pressure.
A problem plaguing all oral gastric lavage systems is clogging of the lavage apparatus, for example, from pill fragments contained in the patient's stomach. A number of methods have been used to attempt to reduce this problem. The above referenced U.S. Pat. No. 5,667,500 describes the use of special, large size, slit valves and back flushing of the lumen tube with irrigant, a procedure not available with the more convenient dual lumen design. U.S. Pat. No. 5,890,516 provides the aspiration valve with a funnel-shaped connector tapering smoothly to a sharp lip to reduce the possibility of particles becoming lodged at the interface between the aspiration valve and a dual lumen lavage tube.
These solutions are not wholly satisfactory and clogging of lavage systems is still common.